DVD5 is a compressed source & thus the quality isnt going to be as good as it can be.
The quality of those screenshots is blurred & check out the jaggies/compression blocks. For such a high res (720x416) with AC3 its been overcompressed. These are stills from relatively motionless scenes, I suspect on high motion its gonna go into block-a-rama like a VCD
I'd vote for low quality